Vapor generator



Aug. 3, 1943. N. c. ARTsAY 2,325,533

VAPOR GENERATOR Filed May 2. 1939 l5 Sheets-Sheet 1 Aug. 3, 1943. N. c.ARTsAY VAPOR GENERATOR 5 shuts-sheet 2' Filed May 2. 1939 Aug. 3, 1943.

4 N. c. AR'rsAY vPoR GENERTOR Filed May n2, 1939 5 Sheets-Sheet 3 ATTNEYAug. 3, 1943;

N. C. ARTSAY VAPOR GENERATOR Filed May 2, 19.39 5 Sheets-Sheet 4 LVMATTORNEY Aug. 3, 1943.

' N. c. /lm'rsw4 VAPOR GENERATOR Filed May 2, 1939 5 Sheets-Sheet 5INVENTOR AOC/,101.46 C: A271570 BY l ff( f( TTORN EYS Patented Aug.3,1943

7 UNITEDV STAT varon GENERATOR menons c. may, vanua, N. Y., mimo toFoster Wheeler Corporation, New York, N. Y., a corporation of New YorkApplication May 2, 1939, Serial No. 271,292

14 claims. (cr 12a-235') This invention relates to vapor generators andmore particularly pertains to steam generators and to circulatingsystems therefor.

The invention provides a steam generator having natural circulationuni-directionally in all pol-tima ofthe heating 4surface, 'and' in whichthere is a minimum disturbance j of the,water levell in the upper drumofthe generator.

'mis is accomplished in general, -by completely isolatingtheadowncomersfrom the gas ilow in the generator to prevent thegeneration of any steam within the downcomer tubes, and byproviding arelatively large number of` downcomer clmnections which are distributedalong the bottom of the upper drum so as to minimize dishirbance of thewater level `in the drum. 'I'he downcomers transfer liquid to the upperendl portion of large vertical manifold headers disposed outside-01' thesetting on each side of the' unit, the lower ends of which dischargeinto horizontally distributing manifolds which ex- 'tend from the frontto the rear of the furnace and connect with the lower headersfor thefront, rear and side water walls. The downcomer system is of adequatecapacity to transfer the full available circulating head of thegenerator between its upper drum and the lowest ends of the heatedelements, to the. lowest water distributingheaders without undueresistance at the required rate of water ilow.

The advantages of the invention include a line 5-'5 of Fig. 2.

right and left hand portions of which are taxen respectively on linesllt-4a and lr-4b of Fig. -2,

Fig. 5 is a horizontalsectional view taken o n Like characters ofreference parts throughout the several views.

Referring to the drawings, reference character I I Il designatesgenerally a steam generator having a setting` formed by steel-encasedrefractory side walls Ii'and I2, and end walls I3 and I4, and

having generally the configuration of a rectangular parallelopiped. Anupper separating or steam and water drum I 5, and a lower drumiii areconnected by spaced groups-of steam generating tubes I'I. I8 and I9.-Adjacent the tubes I8 and extending` downwardly from the drum I5 to apointshort of. drum I6, is a vertical baille 2U, and spaced therefromand adjacent the innermost row of the group of tubes I9 is a verticalbaille 2| similar to baille 20 but extending somewhat further towarddrumV IB. These bailles provide a chamber 9be twee'n'them which .isisolated from the gas'flow, as will hereinafter appear, and in which aredisposed the boiler downcomers 22. 'I'hese downcomers are connected atspaced intervals to drum minimum disturbance of the water level in thesteam drum, the prevention of any steam liberation in the ldowncomers,maximum head for circulation, low differential between maximum tubetemperature and saturation temperature, and

positive circulation in one direction.

These and other advantagesof the invention and the featuresof noveltywhich characterize the invention will be apparent from the followingdescription considered in connection with the Land in which:

I5 along the bottom thereof and for the greater part of the centralportion of its length. Each downcomer extends downwardly from'thelower-v most portion of drum I5 and makes a ,90 turn within the chamber9 and thereafter extends horizontally to, and through, the end wall ofthe setting to a largemanifold header which extends vertically outsidethe setting and adjacent thereto. 'I'he downcomers are symmetricallyarranged in two groups with respect to a vertical plane passingtransversely through the center of drum I5, and the tubes in each groupare arranged in nested relationship as shown in Fig. 3. One group onlyof downcomers is shown in'Fig. 3, but it will be understood that theleit'hand group is similar to the right hand group but oppositelydisposed. 'Ihe outerl ends of the right hand group of downcomers areconnected to a manifold header 23 and the outer ends of the left handgroup connect with a manifold header 24. The number and the capacityofthe downcomers 22 and the capacity of the manifold headers 23 and 24is such as to transfer the available circulating refer tothe. samey -vmanifold header 23 is connected at its lower end to the central portionof an external, horizontally extending distributing manifold or header25, which extends-for the full width of the setting adjacent the lowerportion of each wall I4, and header 24 has its lower end connected tothe central portion of a horizontal manifold or header 26 which extendsfor the width of the setting outside end wall I3. A plurality of tubesv21 connect the header 25 Ywith a horizontal end wall header 29 which isdisposed outside of end wall I4 and adjacent thereto and below header25, while a similar group of tubes 28 connects the header 25 with ahorizontal end wall header 30 also disposed outside of wall I4 andadjacent thereto and at a higher elevation than header 29. Tubes 21 and28 are connected in alternate relationship with each other along thegreater part of the manifold-header 25. A similar circulatoryarrangement; is provided at the opposite endof the setting, adjacent andoutside end wall I3. Tubes 3| connect header 26 with header 33 and tubes32 connect header 26 with header 34.

Additional horizontallydisposed headers 35 and 36 are located at a lowerelevation than the headers 29, 30, 33 and 34 and belowthe'lower ends ofthe vertical walls of the setting. These headers extend at right anglesto the manifold headers 25 and 26 and are located at opposite sides ofand adjacent a vertical plane passing through the axes of the verticalheaders 23 and 24. Header 35 is connected to headers 25 and 26, to theformer by a group of bent tubes 31 and tothe latter by a group of benttubes 38, each group of tubes being arranged and disposed to supplywater to half of the header 35. Likewise header 36 is connected toheaders 25 and 26, to the former by a group of bent tubes 39 and to thelatter by a group of bent tubes 40.

From the headers 35 and 36, which are disposed q substantially below thebottom of the furnace chamber 42, groups of tubes 43 and 44 respectivelyextend upwardly a short distance and then turn outwardly toward theadjacent side wall and thereafter extend horizontally in closely spacedrelationship to the side walls I I and I2 respectively, thus forming awater cooled furnace floor 45 having a central slag discharge opening46.- The tubes 43 then turn vertically upwardly and line the entireinner surface of the lower portion f side wall I 2 between the floor ofthe furnace and horizontal wall headers 41.and 48 to which the upperends of these tubes arealternately connected. Similarly the water walltubes 44 line the inner surface of the lower portion of the side wallII, and are alternately connected at their upper ends toI headers 49 and50. However, as indicated at I, certain of the tubes 44 are bentinwardly from the wall I I and laterally for a substantial portion oftheir length, to provide intertube spacesfor the firing of the fuelburnersv 4I which extend through the side wall II and between the tubes44 in the lower part of the furnace. From the headers 41 and 48, tubes52 extend upwardly and inwardly of the furnace 42 and are connected attheir upper ends .to the lower portion of the drum I6. From the headers49 and 58 water wall tubes 53 extend upwardly and are alternatelyconnected at their upper ends to two similar headers 54 Aand 55respectively at the top of the setting, and line'the inner surface ofthe upper portion of the side wall LI.' A plurality of roof tubes 56connect the headers 54 and 55 with the steam and Water drum I5.

' I4 which is adjacent side wall II, and tubes 51' line the intermediateportion of wall I4. tubes 51 of the group which is located adjacent theside wall I2, are connected at their upper ends 65 which line wall I3,and steam and water is to a relatively short horizontal header 58, whichis positioned'in the wall I4 'at a level slightly below that ofthe drumI6. The header 58 is connected with the drum I5 by a group of externalriser tubes59. The water wall tubes 51 are alternately connected attheir upper ends to horizontal headers 60 and 6I whichy are located atan elevation intermediate the headers 58 and the drum I5. Headers 60 and6I are connected to drum I5 by a plurality of upwardly extending tubes62. Water wall tubes 51, adjacent the side wall I I,extend upwardly toand connect with headers 63 and 64 in the upper portion of the settingandthe headers 63 and 64 are connected to the drum I5 by circulatingtubes 65.

The inner surface of the end wall i3 is similarly lined by three groupsvof closely spaced vertical water wall tubes 66, 66 and 66 whicharealternately connected at their lower ends to the headers 33 and 34, andwhich at their upper ends are respectively connected with the drum bymeans of intermediate headrs 61, 68, 69, and 1I), 1I, the entirearrangement being similar to the' arrangement for the opposite wall I4.A baille 'l2 disposed on or adjacent tubes I1 and extending from drum I6upwardly to a point short of the elevation of headers 63 and 64 provideswith the wall II, a first pass for the gases leaving the furnace. Uponleaving the first pass, the gases flow downwardly through the secondpass between bailles 12 and 20 over a. superheater I3 disposed in thesecond pass, and upon leaving the second pass, the gases ow upwardlythrough the third pass between the baille 2i and the wall I2 to the gasoutlet 14 and then to an economizer or other heat recovery apparatus,not shown.

The baiil's 20 and 2I completely isolate the down- I comer tubes 22 fromcontact with gases flowing through the setting, and no steam generationwill take place within these downcomer tubes at any point throughouttheir lengths.

In operation, water flows from the steam and water drum I5 into andthrough the large number of downcomers 22 to the vertical externalmanifolds 23 and 24, which convey the water to the horizontal externaldistributing headers 25 and 26. Water then flows from manifold 25through pipes 21 and 28 to headers 29 and 30 and thence into the waterwall tubes 51 which line wall I4, and steam and water is conducted fromthe upper ends of these tubes into the steam and water drum I5 throughthe headers 58, 66, 6|, 63 and 64, as previously described. Similarly,water ows from manifold 26 through pipes 3l and 32to headers 33 and 34and thence into tubes conducted from the upper ends of these tubes intothe drum I5 through headers 68, 69, 'I0 and 1 I. Water is also conductedfrom manifolds 25 and 26 through pipes 31 and 38 to header 35 from whichwater is supplied to tubes 43 which line wall l2. lSteam and Water isdelivered from the upper ends of tubes 43 to lower TheV drum II throughheaders 41 and Il. Water ls further conducted from manifolds Il and Ilthrough pipes 3l and 4l to header Il from which water is supplied'totubes u which line wall Il. Steam and water is delivered from the upperends of tubes M to the steam and water drum i! through headers 4I andIl, tubes I3, headers v'fer the available circulating head to the lowestportion of the circulating system without undue resistance at therequired rate of water flow.

Hence a positive upward circulation is produced and maintained at alltimes throughout all the tubes` of the water wall surfaces as well as inthe several tube groups which connect the drums i! and It. The downcomerarrangement permits the installation vofa large number .of downcomers,the drum connections of which open well under the surface of the waterand thus precludes the entrainment of steam through eddies and reducesthe ebullition which normally takes place in saturated vwater upon itsmovement at an accelerated rate into tubular members.

VThe eifectiveness of a circulatory system embodying the invention inpreventing overheating of any of the tubes has been demonstrated by thefact that numerous temperature readings made with thermo-couple wirespeened into the tubes of a full sized unit' embodying the inventionshows a maximum tube temperature of only 50 degrees above the saturationtemperature corresponding to the pressure of the unit.

The form of the invention herein disclosed is a preferred .form andsince various changes may be made in the form, location and relativearrangement of the several parts thereof without departing from theprinciples of the invention.'

it will be understood that the invention is not to be limited 4exceptingby the scope of the appended claims.

What is claimed is:

1. A vapor generator comprising a setting, a furnace, a drum in theupper part f the setting, vapor generating tubes in the setting andconnected in the generator circulatory system with the drum, meansproviding a chamber in the setting below the drum and outside the pathof the gases produced` in the furnace in their ow through the setting,downcomers connected to vthe bottom portion of the drum and along asubstantial portion of the length -thereof and disposed ln said chamber,and a manifold header outside the setting, the `downcomers extendingfrom said chamber through the wall of the setting and connecting withthe manifold header at one end portion thereof, the other end portion ofthe manifold header being connected with the lower portion of thecirculating system of the generator.

2. A vapor generator comprising a setting, aV

furnace, a drum in the upper part of the setting, vapor generating tubesin the setting and condowncomers connected to the bottom portion ofthedrumandalongasubstantialportionofthe length thereof and disposed insaid chamber, and a manifold header outside the setting. the

downcomers extending from slid Chamber through the wall of the setng andconnecting with the manifold header at one end portion thereof, theother end portion of the manifold header being connected with the lowerportion of the furnace water wall.

3. A vapor generator comprising a setting, a furnace, a drum in theupperpart of the setting, vapor generating tubes inthe setting and connectedin the generator circulatory system with the drum, water walls for thefurnace, means providing a chamber in the setting below the drum andoutside the path of the gases produced in the furnace in their ilowthrough the setting. downcomers connected to the bottom portion of thedrum and along a substantial portion of the length thereof and disposedin said chamber, and a manifold header outside the setting, thedowncomers extending from said chamber through the wall of the settingand connecting with the manifold header at one end portion thereof, theother end portion of the manifold header being connected with the lowerportions of a plurality of water walls.

4. A vapor generator comprising a setting, a

furnace, a drum in the upper part of the setting, a second drum in thesetting at a lower elevation than the other drum, vapor generating tubesin the setting' connecting the drums, a water wall for the furnace.means providing a chamber in the setting substantially intermediate saiddrums and outside the path of the gases produced in the furnace in theirflow through the setting, downcomers connected to the lower portion ofthe drum and disposed in said chamber, a manifold header outside thesetting and connected to the downcomers at one end portion, the otherend of the manifold header being connected to a distributing header, andconduits connecting the distributing header with the lower portion ofsaid water wall.

5. A vapor generator comprising a setting, a furnace, a drum in theupper part of the setting,

a second drum in the setting at a lower elevation than the other drum,vapor generating tubes plurality 0f said Water Walls.

nected in the generator circulatory system with the drum, a water wallfor the furnace, means providinga chamber inthe setting below the drumand outside the path of the gases produced in. the furnace in their flowthrough the setting,

6. A vapor generator comprising a settlng, a furnace. a drum in theupper part of the setting, a second drum in the setting at a lowerelevation than the other drum, vapor generating tubes in the settingconnecting the drums, water walls for the furnace. means providing achamber in the setting substantially intermediate said drums and outsidethe path of the gases produced in the furnace in their flow through thesetting, downcomers connected to the lower portion of the drum v anddisposed in said chamber, a manifold header outside thev setting andconnected to the downcomers at one end portiomthe other end of themanifold header being connected to a distributing header, and conduitsconnecting the distributing header with the lower portion of more thantwo of said water walls.

'1. A vapor generator comprising a setting, a furnace, a drum in theupper part of the setting, a second drum in the setting at a lowerelevation than the other drum, vapor generating tubes connecting thedrums, a, water wall for the furnace, means providing a chamber in thesetting adjacent tubes connecting the drums and outside of the path ofthe gases produced in the furnace in their ow through the setting,downcomers connected. to the bottom portion of the drum and along asubstantial portion of the length thereof and disposed in said chamberand extending through a Wall of the setting, a manifold header outsidethe setting having its upper' end portion connectedfto the downcomersand having its lower end portion connected to the lower portion of thewater wall.

8. A vapor generator comprising a setting, za'A f the drum and disposedin said chamber and extending through a wall of the setting, a manifoldheader outside the setting having its upper end portion connected to thedowncomers and having its lower end portion connected to the lowerportion of the water wall.

9. A vapor generator comprising a setting, a furnace, a drum in theupper part of the setting, vapor generating tubes in the setting andconnected in the generator circulatory system with the drurn, waterwalls for the furnace, means providing a chamber in the setting outsidethe p ath of the gases produced in the furnace in their ow through thesetting, downcomers connected to the lower portion of the drum anddisposed in said'chamber, one group of downcomers extending through thewall of the setting at one end of the chamber and another groupextending through the wall of the setting at the other end of thechamber, and manifold headers outside of the setting each having: itsupper end portion connected to one group of downcomers and having itslower end connected to the lower portion of at least one of said waterwalls.

10. A vapor generator comprising a setting, a furnace, a drum in theupper part of the setting, vapor generating tubes in the setting andconnectedI vin the generator circulatory system with the drum, waterwalls for the furnace, means providing a, chamber in the setting outsidethe path of the gases produced in the furnace in their ow through thesetting,` downcomers connected `to the lower portion of the drum anddisposed in said chamber, one group of downcomers extending through theWall of the setting at one end of the chamber and another groupextending through the wallof the setting at the other end of thechamber, manifold headers outside of the setting each having itsupperend portion connected to one group of downcomers and having its lowerend connected to a distributing header, and means connecting eachdistributing header to the lower portion of at least one of said waterwalls. I

11. A vapor generator comprising a setting, a furnace, a drum in theupper part of the setting, vapor generating tubes in the setting andconnected in. the generator circulatory system with the drum, waterwalls for the furnace, means providing a chamber in the setting outsidethe path of the gases produced in the furnace in their ow through thesetting, downcomers connected to the lower portion of the drum anddisposed in said chamber, one group of downcomers extending through thewall of the setting at one end of the chamber and another groupextending through the Wall of the setting at the other end of thechamber, manifold headers outside of the setting each having its upperend portion connected to one group of downcomers and. having its lowerend connected to more than two of said water walls.

12. A vapor generator comprising a setting, a substantially rectangular-furnace in the setting, a drum in the upper part of the setting, vaporgenerating tubes in the setting and connected in the generatorAcirculatory system with the drum, a water wall for each of the verticalwalls of the furnace, means providing a chamber in the setting outsideof the path of the gases produced in the furnace in their flow throughthe setting, downcomers connected with the lower portion of the drum anddisposed in said chamber, one group of downcomers extending through theWall of the setting at one end of the chamber and another groupextending through thewall of the setting at the other end of thechamber,manifold headers outside the setting each having its upper endportion connected to one group of downcomers and having its lower endconnected to a distributing header, each of said furnace water wallshaving a lower header, and conduits connecting each distributing headerwith at least one of the lower headers of the furnace Water walls.

13. A vapor generator comprising a setting, a substantially rectangularfurnace in the setting, a drum in the upper part of the setting, vaporgenerating tubes in the setting and connected in the generatorcirculatory system with the drum, a water wall for each of the verticalwalls of the furnace, means providing a chamber in the setting outsideof the path of the gases produced in the furnace in their now throughthe setting, downcomers connected with the lower portion of the drum anddisposed in said chamber, one group of downcomers extending through thewall of the setting at one end of the chamber and anothergroup extendingthrough the wall of the setting at the other end of the chamber,manifold headers outside the setting each having its upper end portionconnected to one group of downcomers and-having its lower end connectedto a distributing header, each o1' said furnace water walls having alower header, and conduits connecting each distributing header 'withthree of the lower headers of the furnace water Walls.

` 14. A yvapor generator comprising a setting, a su-bstantiallyrectangular furnace in the setting, a drum in the upper part of thesetting, vapor generating tubes in the setting and connected in thegenerator circulatory system with the drum, a water wall for each of theVertical walls of the furnace, means providing a chamber in the settingoutside of the path of the gases produced in the furnace in their flowthrough the setting, downcomers connected with the lower portion of thedrum and disposed in said chamber, one group oi downcomers extendingthrough the wail of the setting at one end of the chamber and anothergroup extending through the wall of the setting at the other end of thechamber, mani- -fold headers outside the setting each having its upperend portion connected to one group o! downcomers and having its lowerend connected to a. distributing header, each of said furnace waterwalls having a lower header, conduits connecting each distributingheader with the lower header of one water wall along substantially itsentire length, and other conduits connecting each distributing headerwith one end portion of each of the lower headers of two other Waterwalls.

NICHOLAS C. ARTSAY.

